Railroad or other spike.



Patented Nov. ll, I902.

E 1 '1 D10 m M e U Tu TGJ S m m J .D w HAM 8 n A on I 2 5 3 7 n N (NoModel.)

' INVENTOIB.

harm. avg/(,

ATTORNEY WITNESSES:

UNTTnn STATES PATENT OFFICE.

HENRY J. STONE, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY MESNEASSIGNMENTS, OF TVVO-THIRDS TO J. WV. MACAULAY, OF SAN JOSE,

CALIFORNIA.

RAILROAD OR OTHER SPIKE.

SPECIFICATION forming part of Letters Patent N 0. 713,527, datedNovember 11, 1902.

Application filed June 17; 1901.

To (all whom, it incty concern:

Be it known that I, HENRY J. STONE, a citizen of the United States,residing at San Francisco, in the county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements inRailroad or other Spikes, of which the following is a specifica' tion.

My invention relates to improvements in spikes for railroad or otherpurposes, the object of my invention being to provide a spike which willhave greater holding force for the same size than those heretofore inuse.

In the accompanying drawings, Figure 1 is a side elevation of myimproved spike. Fig. 2 is a longitudinal section of the locking-head ofsaid spike. Fig. 3 is a similar View, the spike being removed. Fig. 4 isa plan view of said locking-head. Fig. 5 is a side elevation of the headof the spike. Fig. 6 is a rear view of the locking-head. Fig. 7 is aview of the point of said spike. Fig. 8 is a crosssection in the line AA of Fig. 1. Fig. 9 is a side view, partly in section, of amodification. Fig. 10 is an end view of the point of the spike, showingthe construction of the twin cutters.

Referring to the drawings, 1 represents the shank of the spike,cylindrical in form. In said shank are out two threads or spiral groovesThe bottom of each groove is in cross-section a continuous concavecurve, as shown in Fig. 8. Each thread is of such a pitch as to make buta single turn in the whole length of the shank. Each thread terminatesin a cutting edge the rear of which is rounded off into the outercylindrical surface of the shank, the two cutting edges corresponding tothe two threads being diametrically opposite to each other, as shown inFig. 10. The head 5 of the spike is made cylindrical in form, and on theunder surface of said head are formed locking-teeth 6, adapted to engagesimilar teeth '7, formed in the bottom of a cylindrical socket 8 in thelockinghead 9, in which socket the head 5 fits snugly. Said locking-head9 may be of any size and is formed with a lip 10, curved on its underside, as shown at 11, to rest upon the curved flange of the rail, and onthe back side of said head are two projections 13, which when Serial No.64,951. (No model.)

the spike is driven down are adapted to embed themselves firmly in therailroad-tie. One way in which the present railroad-spikes become looseis that by the outward pressure of the rails, particularly in a curve,the tops of the spikes are pressed laterally away from the track andagainst the wood and cut into the wood of the tie. The projections 13 onthe back of locking-head being embedded in said tie tend to prevent thisrearward movement.

In operation when the compound head is placed upon the tie in properposition the points or projections on the back end are pressed into thetie to hold it while the spike is being driven. The spike is then driventhrough the compound head into the tie by blows, and in its downwardmovement it turns, by reason of the thread 2, makinga completerevolution, so that in its final position when driven home into the tiethe lip of the locking-head lies upon the flange of the rail in theproper position to hold same firmly to the tie.

The teeth 6 7 prevent the head from turning relatively to the spike andthey are also advantageous in the following respect: Rails are apt tobecome loose by the partial withdrawal of the spike, caused by thespring of the rail after the train has passed thereover. The passage ofa train causes the rail to spring, and when the train has passed overthe rail springs up again, drawing with it the spike and partly pullingit out of the tie unless said spike is embedded in the tie withsufficient firmness. The teeth permit the trackman, in case the railwears into the tie,which would loosen the compound head, to strike thehead 5 of the spike,which will turn and take up one notch or more in thecompound head, which is stationary, but which draws the tie up to itsproper place against the rail.

An important feature of my invention consists in the extension of therear end of the compound head, which may extend any desired length. Thislateral extension resting upon the tie prevents the bending of thespike.

In the modification shown in Fig. 9 the head is made integral with thespike, and in this case the head may be made of the usual form.

It has been found by actual tests of this improved spike that muchgreater force is required to withdraw it from the tie than with thecommon spike. Thus while the common four-inch railroad-spike came outentirely at a pull of eleven hundred and forty-seven and one-half poundsa double-threaded spike of the same size constructed according to myinvention started under a pull of two thousand and sixty-seven andone-half pounds. Moreover, while the common spike came out without anyfurther pull the improved spike required a pull up to the last point andrequired nearly one hundred pounds more to finally withdraw it.

It is found that aspike of this character cannot be unscrewed. Animportant feature of the invention is that the action of the spike uponthe wood is different from that of a common-cut nail or railroad spike,for while the latter forces a certain proportion of the wood downwardthe improved spike only displaces it laterally, leaving two solid coresfrom the point to the head. Another important feature resides in theshape of the point of the spike, which comprises cutting points on bothsides, the rear of the points being rounded off", and thereby permittingthe spike to enter freely and displacing the wood laterally, whereas thepoint of the common twist-drill, which this resembles,cuts into smallparticles the iron or wood into which it penetrates.

I am aware that it has been proposed to make a twist-drill with a pointhaving cutting edges on both sides in line with each other, the rear ofthe edges being rounded off; but this feature alone is not sufiicient topermit the spike to be driven into the wood at a single blow and to turnitself when so driven. In order that this can be done, it must benecessary that the thread should make a single turn only for the wholelength of the spike. It is necessary to provide the spike with a threadof a very slow pitch in order to permit the spike to be driven in by ablow and at the same time turn itself in the wood. A further differenceis that the twist-drill above referred to if used with a wooden tiewould tear or cut the fiber of the wood, while my improved spike doesnot cut the fiber, but only displaces it. This difference is due to thepitch of the thread. I am also aware that it has been proposed to make arailroad-spike the thread of which makes a single turn in the wholelength of the spike; but this construction again was inefiective, onaccount of the form of the point of the spike, said point being achisel-edge extending the whole width of the spike. With such a pointthe spike will not turn itself when driven by a blow, since the cuttingedge tears or cuts the wood instead of displacing it.

In order to provide a spike which can be driven in at a single blow andwill turn itself once around when so being driven in and which will onlydisplace the wood instead of cutting it, so that the wood binds tightlyin the two grooves of the thread and exerts a powerful resistanceagainst removal, it is necessary, first, that the spike should have apoint formed with two cutting edges in line with each other on oppositesides of the center, the rear of each cutting edge being rounded 05,and, secondly, the spike should have two threads, each of which shouldhave a single turn in the whole of the length thereof. If either ofthese properties is absent from the spike, it will not do the workrequired.

It will be understood instead of two projections 13 on the rear side ofthe spike-head a single projection in the center may be used, ifdesired, to better allowapinch-bar to grasp the compound locking-head incase the spike has to be drawn.

I claim- 1. A spike for railroads comprising a shank cylindrical in formhaving cut therein two grooves or threads, the bottom of each groovebeing a concave curve in cross-section, each thread making onlya singleturn in the whole length of the stroke, each thread terminating in acutting edge, the rear of each cutting edge being rounded off into thecylindrical surface of the spike, and the two cutting edges being inline with each other on opposite sides of the center, substantially asdescribed.

2. A spike for railroad or other purposes havinga threaded shank and ahead, and having also a locking-head entirely surrounding said shank andabutting against the under surface of the head, said locking-head havinga lip curved on its under side to rest upon the curved flange of therail, substantially as described.

3. A railroad-spike having ashank 1 formed with the threads 2 and acylindrical head 5 and a locking-head 9 having a cylindrical socket 8 inwhich the head 5 fits snugly, said locking-head being formed with a lip10 curved on its under side and having on the back side of the head thetwo projections 13 arranged to embed themselves in the railroad-tie,substantially as described.

4. A spike for railroad or other purposes having a threaded shank and adetachable head, the top of said spike and said head having teethengaging each other to prevent rotation of said head around said spike,substantially as described.

In witness whereof I have hereunto set my hand inthe presence of twosubscribing witnesses.

HENRY J. STONE.

